Nailing machine



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NAILING MACHINE Original Filed Jan. 26. 1920 5 Sheets-Sheet Patented -May 3, I927.

UNITED STATES PATENT- OFFICE.-

I ELMER O. NORTHRUP, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR, BY MESNE AS- SIGNMENTS, TO SPRAGUE-SELLS CORPORATION, OF HOOPESTON, ILLINOIS, A COR- PORATION OF DELAWARE.

NAILING MACHINE.

Original application filed January 26, 1920, Serial No.

December 17, 1923.

My invention relates to machines for driv-' ing nails.

An object of the invention is to provide a nailing machine in which are incorporated 5 improved means for feeding the nails to the chucks.

This application is a division of my Patent 1,478,362.

The invention possesses other objects and 1 features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of my invention which is illustrated in the drawings accompan ing' and forming part of the 1 specification. It is to be understood that I do not limit myself to the showing made by the said drawings and description, as I may adopt variations of the preferred form within the scope of my invention as set forth in p 2 the claims.

Referring to the drawings:

Figure l is a front elevation of the nailing machine of my invention.

Fig. 2 is a. right side elevation of the machine, certain of the parts being omitted for greater clearness.

Fig. 3 is a rear elevation of the machine, showing the parts when the hammers are raised.

Fig. 4 is a rear elevation of the upper, portion of the machine showing the parts when the hammersare in lowest position.

Fig. 5 is a horizontal sectional view taken in the plane 55 of Fig. 3.

Fig. 6 is a front elevation of two of'the nail feeding arms and related mechanism.

Fig. 7 is a right side elevation of the structure shown in Fig. 6.

Figs. 8 and 9 are plan views of portions of the nail chutes and show nail feeding means in two successive positions.

Fig. 10 is aleft side elevation of the upper front portion of the machine, showing the nail feed operating means.

For convenience of descriptionmy nailing machine may be considered as comprising the following groups of mechanism.

1. A frame upon which the various instrumentalities are mounted and co-ordinated to operate as a unit of mechanism.

2. A table resiliently supported on the frame, and upon which the box or other 354,070. Divided and this application filed Serial No. 681,054.

work to be nailed is positioned against suitable gauges.

A hammer bracket mounting a plurality of hammers for driving the nails from the chucks into the box, and also adjustably spaced nail chucks for holding the nails immediately prior to driving, together w1th means for suspending the nail chucks from the hammer bracket so that the engagement of the chucks with the work about to be nailed is substantially coextensive with the driving of the nail.

4. Power driven means, the action of which is pedally initiated for actuating the hammer block.

5. Means for automatically disconnecting the power supplying means from the hamnier block actuating means at the conclu sion of each nailing operation; and automatically operating means for-controlling the momentum of the moving parts'of the driving means, so that such driving means will come to rest in substantially the same position after each nailing operation.

6. Means for feeding nails to all or' certain of the chucks as required.

Undersubtitles briefly identifying these groups and in the same order, I will now deslcribe the construction of my device in detai Frame.The frame of the machine comprises a bed plate 2 adapted to rest on the floor and from which two spaced posts 3 and 4 extend upwardly to the cross piece 6. Extending upwardly from the cross piece, and slanting slightly to the left are two other spaced posts 7 and 8 joined at the top by t e cross piece 9.

TabZe.Vertically slidably arranged on the flanged edges 11 of the posts 3 and 4 is a table 12 upon which the work 13 is supported. The table is additionally supported on the post 14 which is vertically adjustable by means of the threaded collar 16 in the socket 17 arranged on the bed plate 2. The upper end of the post is slidably disposed in the socket 18 on the under side of the table, and is threaded for the nuts 19 which prevent the table from being forced off the post 14 by the heavy spring 21 interposed between the bottom of the socket 18 and the collar 22 on the post. Thus the table is its adjusted level during the operation of ment with the head of the stud 44. Therethe machine to compensate for variations in the material or adjustments. Gauges 23 and 24 adjustably secured to the table. by screws, provide means for positioning the work thereon.

H ammcr bracket and c7uw7cs.Slidably mounted on the flanged edges 26 of the frame posts 7 and 8 is the hammer bracket 27 adapted to be reciprocated by connecting rods 28, one of which is arranged on each end of the hammer bracket, as shown in Fig.

1, and which are actuated by cranks 29 onv the shaft 31. Secured to the hammer bracket are hammer rods or hammers 32 adjustably arranged on the bracket by means of the ingly formed edge of the hammer bracket 27 and retained therein by {the plate 34. .The-

ends of the hammers extend into chucks 36 of known construction into which nails are fed as needed. Each chuck is provided with abolt 37 adapted to engage in a T-slot 38 formed in the chuck bracket 39, so that the chucks may be spaced to give the desired spacing of the nails. The chuck bracket is also slldably mounted on the flanged edge 26 of the frame posts 7 and 8, and 1s operatively connected to the hammer bracket so that it falls to permit gravital engagement of the ends of the chucks with the work, just prior to the application of the driving force upon the heads of the nails by-the ham 7 mers, and rises again to firstposition with the initial upward movement-of the hammer bracket. This character of movement 'is of great importance since it permits the longest possible interval between successive nailing operations for the removal and placing of the work. This connection is supplied by spaced arms 41 pivoted to the chuck bracket and resiliently drawn together by the coiled spring 42. The arms are bent so that their upper portions are inclined sharply toward each other, the inclined portions engaging on their adjacent edges, rollers 43 mounted on studs set in the hammer bracket. A stud 44 fixed in the cross piece 6, and passing loosely through a lug 46 on the chuck bracket limits the upward movement of the chuck bracket. -With the hammer and chuck brackets in their upper positions as shown in Figs. 1, 2 and 3, the chuck bracket is pendantly supported from the hammer bracket by the arms 41 strongly and resiliently engage-d against the rollers 43. Owing to the slant of the arms, there is a vertical component of the force exerted by the spring, which tends to cause the two brackets to approach each other. Downward movement of the hammer bracket is controlled by the connecting rods 28, and the chuck bracket cannot move upwardly owing to its engage of the tension of the spring 42, the effective weight of the chuck bracket balances or exceeds the verticalcomponent of the spring tension, whereupon the chuck bracket also falls, engaging the ends'of the chucks with the Work to be nailed. The parts are now as shown in Fig. 4, the rollers 43 lying in the bend of the arms. When the hammer bracket begins its upward movement, the chuck bracket is pickedup at substantially the same moment owing to the resilient engagement of the arms 41 with the rollers,

and the fact that the vertical component slotted heads 33 engaging the correspondof the spring tension is greater than the force restraining the upward movement of the chuck bracket, as soon as the rollers engage the edges of the upper bent portions of the arms. lVhen the chuckbracket reaches the limit of its upward movement as determined by the stud 44, it stops, the hammer bracket continuing to the top of its stroke, against the resistance of the arms 41 which are thereby spread apart as shown in Fig. 3. Preferably pins 47 are fixed in the ends of the arms, adapted to engage the top edge of the hammer bracket if the spring 42 should fail. In order to drive the nails at a slight angle, the posts 7 and 8 on which the ways 26 are formed are inclined at the desired angle as shown particularly in Figs. 1 and 3. Gauge 49 for facilitating the placmg of the work is secured to the'under side of the chuck bracket.

Ham/mar driving means.Journalled in suitable bearings arranged on the bed plate of the frame is the main driving shaft 51 upon which a driving pulley 52 is rotatably ,mounted. The pulley is connected by a belt 53 with any suitable source of power. Interposcd between the pulley and the shaft 51 is a clutch mechanism of known form including the sleeve 54 splined upon the shaft, and longitudinally movable thereon by means of the yoke 55 operated by the pedal 56. A pinion 57 on the shaft 51 drives gear 58 on the shaft 31 on which the hammer block operating cranks 29 are fixed. Downward pressure on the pedal 56 therefore engages the clutch mechanism with the pulley, and causes the shafts 51 and 31 to rotate, the latter shaft atrelatively low speed. One revolution of the shaft 31,1owers the hammer block to drive the nails in the chucks and raises it again to first position.

Means for disconnecting the driving pul- Zey and brake.Since each nailing operation must be followed by the removal of the work and the positioning of new work, it is desirable to bring the operation of the nail driving mechanisms to a halt immediately following each nailing operation.

'to rest in substantially the same position each time, with the cranks 29 at the top of their stroke. Fixed rigidly on the shaft 31 is an arm 59, Figure 5, the end of which is adapted to engage a cam surface 61 of a lug 62 formed on one side of the yoke 55. With the parts at rest and the clutch sleeve 54 in the disengaged position, the arm end lies just below and to one side of the lug 62. lVith the throwing in of the clutch, the sleeve moves over to the left (of Fig. 5) and the cam surface 61 then lies in the path of the arm 59 which simultaneously began to rotate with the shaft 31. Nearing the end of one complete revolution of the shaft 31, the arm end engages the cam surface and forces the yoke to the right (of Fig. 5) thus freeing the clutch. Braking means are also brought into operation at this moment for controlling the momentum of the rotating parts. Fixed on the shaft 51 is a brake drum 63 adapted to be frictionally engaged by the pivoted brake lever 64 curved to fit the drum and provided with a suitable lining. A bellcrank lever 66 is pivoted to the frame and provided with a roller 67 on oneof its arms bearing on the crank arm 29 which in this relation acts as a cam to impart motion to the lever 66. The other arm 66 of the bellcrank lever is provided with an adjustable screw 68 adapted to engage a spring pressed pin. 69 held in the end of the brake lever. Thus rotation of the crank arm 29 to its topstroke position operates the lever 66 and resiliently forces the brake 6 1 against the drum. The degree of resilient pressure and the point at which the braking action is initiated being determined by adjustment of the screw 68. The parts are so adjusted that the clutch is freed and the brake applied to bring the rotation of the shaft 31 to a halt with the cranks 29 at the top of their stroke and the hammer block in the raised position as shown in Fig. 2.

[Vail feeding means-The machine may be arranged to drive any desired number of nails at one time. The drawings show a machine with seven chucks and capable of driving seven nails or a less number at one time. Means are provided for feeding nails to the nail chucks in accordance with the need of the nailing mechanism and no nails are fed to chucks from which a nail is not to be driven.

Fixed on the cross arm 9 of the frame is a bracket 71 in which a series of nail chutes 72 are arranged in a known manner. A nail box 73 of known construction into which the supply of nails is thrown is pivoted to the bracket 71 and vibrated to shake the nails into the chutes, by a rod 74 connected to a crank 76 fixed on the shaft 77 which is rotated by the sprocket wheel 78. A chain 7 9 connects this sprocket with sprocket 81 on shaft 82 with the large gear 83 which meshes with a pinion 84 arranged on the side of the driving pulley 52. Thus the nail box is vibrated by the rotating pulley 52 irrespective of the operation of the other mechanism so that the nail chutes are kept filled. Below the end of each chute is a funnel 86 adjustably secured to the bracket 71, and connected by flexible *conductors 87 to the nail chucks.

Pivotally mounted on the bracket 71 in front of the lower end of eachnail chute is a feed arm 88, the upper end of'which is formed to provide a cam edge 89 to be engaged by a roller 9l,disposed on a pin 92 set in a shaft 93. The shaft is journalled in bearings arranged on the bracket 71 and is given an intermittent rocking motion by means of the crank arm-91, (Fig. 10) fixed on the end of the shaft and connected by red 96 to the hammer bracket. Thus each roller is rcciprocated back and forthacross the face of the associated cam 89. Fig. 6 shows a roller 91 at one end of its stroke. With each complete vibration of the shaft, the arm 88 is rocked in a clockwise direction against the pull of the spring 97, from the position shown by the arm 88, (Fig. 6) across the end of the associated nail chute to the position shown by the arm 88, (Fig. 6) and then allowed to return to first position. Secured to the arm 88 by screw 98 is a flat spring 99, prevented from rotating on the screw by guard pieces 101. The end 102 of the spring is bent at rightangles and so disposed as to lie in front of and slightly spaced from a wedge point finger 103 adjustably secured to the lower end of the arm 88 by aclamp nut 10 1.- WVit-h the rocking of the arm as the roller 91 moves upon the cam 89, the finger 103, which normally lies across the end of 'the nail chute as shown in Fig. 9 and at the right of Fig. 6, is first withdrawn to a position shown in Fig. 8, and at the left of Fig. 6, allowing the leading nail 106 to slide downwardly against the end 102 of the spring arm which moved across the chute as the finger 103 was withdrawn. The parts are now in the position shown at the left of Fig. 6 and in Fig.8. As the roller 91 recedes from the cam 89, the lower end of the arm moves back to first position, the wedge point of finger 103 intercepting the second nail 107 and the leading nail 106 dropping out of the end of the chute into the associated funnel, as soon as the end 102 of the spring arm releasing a nail into the chuck for thenext following nailing eration accomplished by the next downwar movement of the-hammer block. Assuming the first nail in a chuck, the first downward movement of the hammer block drives the first nail and releases a second nail which falls into the chuck, the second downward movement of the hammer blockdrives the second nail and releases a third, and so on.

Since each roller 91 associated with a. given feed arm 88 controls the release of a nail, it follows that by removing a roller as in the case shown at the right of Figs. 1 and 6, the associated feed arm is not operative and the associated chuck remains empty. This is done to adapt a machine for driving a less number of nails than its full capacity and is accomplished by removing the cotter pin 108 which normally retains the roller upon its pin. I claim:

1. In a nailing machine a plurality of nail chutes, means for filling said chutes with a succession of nails, means including a pivoted lever for releasing one nail at a time from each of said chutes, a shaft extending adjacent the upper ends of said levers, means for rocking said shaft, and means on said shaft for operatively engaging said levers.

2. In a nailing machine, a plurality of nail chutes, means for filling said chutes with a succession of nails, a lever pivoted adjacent the end of each chute, a rock shaft, means for rocking said shaft, demountable means or said shaft for vibrating each lever, and means on each lever for releasing a nail from the associated chute with each Vibration thereof.

3. In a nailing machine, means for holding the Work .to be nailed, a plurality of chucks for holding nails to be driven, means for driving the nails, a nail chute associated with each chuck, means for filling said chutes with a succession of nails, means associated with each chute for releasing into the associated chuck one nail at a time, a shaft, a plurality of 'demountable means on said shaft for operating said releasing means, and means for rocking the shaft intermittently in time with the operation of the nail driving means.

4. In a nailing machine, means for holding the work, a plurality of chucks for holding nails to bedriven, means for driving the nails, a nail chute associated with each chuck, means for filling said chutes with a succession of nails, means associated with each chute for releasing into the associated chuck one nail at a time, a shaft, a pin fixed on said shaft adjacent each releasing means, rollers demountably and rotatably mounted on said pins for engaging said releasing means, and means for rocking said shaft in time with the operation of the'nail driving means.

5. In a nailing machine, a plurality of nail chutes, means for filling said chutes with a succession of nails, means for releasing one nail at a time from each of said chutes, a shaft, means for rocking said shaft, and demountable means on said shaft for operatively engaging each releasing means whereby a releasing means is inactive in the absence of the associated demountable means.

In testimony whereof, I have hereunto set my hand.

ELMER C. N ORTHRUP. 

